I know they were in some because there were reports of people being cut on set by accident.

I remember on the commentary for X1, Bryan Singer mentioned that Hugh almost crashed into someone during one of the wire stunts in the Statue of Liberty fight, and he'd stuck his hands out to stop the crash, but he'd been wearing the claws and nearly stabbed the guy. No one was hurt, but Singer mentioned that later he needed to talk Hugh into not using the double for the shot where Logan cuts Rogue's hands free from Magneto's machine, because he was really shaken up over it.

That being said...anything but those awful CGI claws, please.

__________________”We live in times when hate and fear seem stronger. We rise and fall, and light from dying embers: remembrances that hope and love last longer. And love is love is love is love is love is love is love cannot be killed or swept aside."